If you want to get Middleton's yellow first-appearance dress for yourself, you'll need to move fast. Like, really fast. In the past, Middleton's dresses (and lookalike versions) have sold out within hours, a phenomenon the Huffington Post describes as the "Kate Middleton Effect." In fact, the blue Jenny Packham dress she wore after giving birth to Prince George (a nod to Princess Diana) was virtually impossible to find after a few hours of her hospital exit.

If you have incredible luck, you might be able to buy a dress similar to Middleton's white and yellow floral Jenny Packham shift before all of the lookalikes sell out, because we have a hunch this is a custom creation for Middleton. Must be nice to be a duchess!

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The exact dress doesn't appear to be for sale (at least, not yet), but here are a few similar frocks to get your hands on now.